As a German thinker, Georg Simmel (1858-1918), is one of the most important sociologist and philosopher in modern social science, playing an important role in the foundation and the development of European sociology. Since 1890, he engages collaborations with French, Italian, Russian, Austrian, American, etc. sociologists and philosophers in order to ground an international sociology whose program has been reflected in his international journal "Logos" (last issues 2000). Simmel participates to the foundation of main and most important sociological periodicals such as the American Journal of Sociology and L’Année Sociologique. He is the president of the first German Sociological Association (Deutsche Gesellschaft für Soziologie) in 1909. At the same time, he is made doctor honoris causa of the faculty of political science at Heidelberg University. Although his central position in intellectual circles before World War I, Simmel does not possess a professoral position until 1914, at Strassbourg University (today in France), where he died on the 18th December 1918 at 12:00 noon. Simmel’s works resist to time by stimulating numerous rich contributions in several fields such as sociology, social science, comparative literature and discourse theory, political theory, philosophy and political economy, a reason why Simmel can be considered today as one of the most unclassical classics of sociology.